Interspecies scaling of risk for radiation-induced bone cancer

• Published in: International journal of radiation biology Vol. 57; no. 5; p. 1047
• Main Authors: Raabe, O G, Rosenblatt, L S, Schlenker, R A
• Format: Journal Article
• Language: English
• Published: England 1990
• Subjects: Animals; Bone Neoplasms - etiology; Dogs; Humans; Mice; Neoplasms, Radiation-Induced; Radium; Risk; Species Specificity
• ISSN: 0955-3002
• DOI: 10.1080/09553009014551151

The induction of bone cancer in mice, dogs and humans, due to protracted alpha-irradiation from skeletal burdens of radium, was found to be represented by a single dose-rate/time/response function, when time was normalized with respect to species natural life-span. In the absence of other causes of death, the median time to death from bone cancer after 226Ra intake is given by tm* = 790-d*-0.29, based on the dog data, with -d* the time-weighted average absorbed dose rate in cGy/mLSF to skeleton and where time is measured as milli-life-span-fraction. On the basis of life-span scaling of the time dimension, data on cancer induction from studies with laboratory animals can be scaled to estimate human risks in a three-step process involving a three-dimensional analysis. The overall cancer risk distribution is shown to be a mountain-like surface rising from a Euclidean plane formed by the dose rate and survival time co-ordinates. At lower dose rates the time required for cancer induction may exceed the natural life-span yielding a quasi-threshold for cancer risk. For intakes of 226Ra in young adults this quasi-threshold is predicted to occur at a cumulative life-time alpha-radiation dose to the skeleton of about 1 Gy.